A novel set-up using immersion coolers from Julabo to regulate temperature in a closed bath is being used for corrosion related experiments at the Nuclear Materials Section within the Applied Chemistry division at Necsa (South African Nuclear Energy Corporation).
Ryno van der Merwe, a Metallurgist in the division required a separate cooling device while testing the corrosion rates of various steels and metallic alloys in hydrofluoric acid. The study aims to define the corrosion characteristics of these metals under a variety of conditions. The influence of temperature on corrosion rates is one major factor and the corrosion data from the study will assist in future material selection of critical plant components. Instead of acquiring a completely new system for this project, immersion coolers were added to their existing baths at a fraction of the cost.
To conduct the experiments, two thermocouple PT temperature probes are being used to regulate and control fluid temperature. The first probe leads from the Julabo immersion cooler situated on the outside of the fume hood to the existing water bath which is situated inside, while an internal PT temperature probe is fitted inside the water bath. A customised protective lid also fits over the water bath which serves to shield all components above water level.
The Julabo immersion cooler, model FT402 is used to rapidly countercool between the ranges of -40°C to 30°C with a temperature stability of 0.5°C. This reading is clearly digitally displayed on the screen of the unit. To ensure no freezing takes place below ambient temperatures, Julabo thermal bath fluids are used inside the waterbath to give the best results in terms of viscosity, heat conductivity and stability. This FT402 unit saves water as no tap water is required for cooling, and it can be used as a substitute for dry ice. This small footprinted compact unit is user-friendly to operate, and gives added piece of mind whilst the experiment is running at the required temperature specifications in a controlled environment, which is especially necessary in regulating and maintaining a constant temperature for the duration of each corrosion experiment conducted.